BoilerFaultCodesYour boiler is providing hot water as usual, but the central heating is failing to turn on, likely due to a communication issue between your controls or a mechanical part inside.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Hot water but no heating
What causes this fault?
This issue typically occurs when the internal diverter valve becomes stuck or the motor that moves it fails, preventing heat from being directed to your radiators. It can also be caused by a breakdown in communication between your wall thermostat and the boiler, meaning the system never receives the signal to start heating. Effectively, the boiler stays stuck in 'hot water mode' even when you are asking for warmth.
This fault often becomes apparent during the first cold snap of autumn when the heating is turned on for the first time after being idle all summer.
DIY fix possible
Ensure your wall thermostat or programmer is set to 'On' and the temperature is turned up higher than the current room temperature.Replace the batteries in your room thermostat if it is a wireless or digital model.Check that the heating temperature dial on the boiler itself is turned up.
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